THE 30 MOST IMPORTANT PRE-SOCRATIC PHILOSOPHERS AND THEIR IDEAS - PHILOSOPHY - 2025

Pre- Socratic philosophers have been perhaps one of the most important generations of thinkers in history. Among its representatives we can find such enlightened philosophers as Thales of Miletus, Pythagoras or Heraclitus.

Pre-Socratic philosophy is defined as that developed before and contemporaneously with Socrates. Aristotle referred to all the thinkers in this group as physikoi, because they sought natural explanations for the phenomena they observed.

Pre-Socratic philosophers rejected the traditional mythological view of the time to provide a more rational explanation of things.

You may also be interested in this list of philosophers from the Ancient Age or this one from the Middle Ages.

List of the most prominent pre-Socratic philosophers

Thales of Miletus

Thales of Miletus (624 BC - 546 BC), born in Miletus (now Turkey), is traditionally recognized as the first Western philosopher and mathematician. He was able to accurately predict the solar eclipse that occurred on May 28, 585 BC and was known as a great astronomer, geometrist, statesman, and sage.

Thales is said to have been the first to wonder about the basic composition of the universe and established that the First Cause was water. It has the ability to change shape and move, remaining intact in substance.

There are no known writings made by Thales and all that is known of his life and work is through what others have written about him.

Heraclitus

Heraclitus of Ephesus (535 BC - 475 BC), born in Ephesus (today Turkey), was known by his contemporaries as the dark philosopher, because his writings were quite difficult to understand.

He is best known for his doctrines that things are constantly changing (universal flow), the attraction of opposites, and that fire is the basic material of the world. In his cosmology, he argues that the world was not created by God or man, but has always been and will exist by itself.

Pythagoras

Pythagoras of Samos (570 BC - 495 BC) was a Greek philosopher and mathematician and founder of a movement known as the Pythagoreans. He made great contributions to philosophy and religion, but is best known for developing the Pythagorean theorem that bears his name.

As a disciple of Anaximander, his vision of astronomy was the same as his tutor's. Many of the achievements that are credited to him were in fact carried out by his colleagues and successors.

There are no known writings made by him and most of the information that is known about him was compiled by other people over the centuries.

Parmenides

Parmenides of Elea (b. 515 BC) was a Greek philosopher born in the colony of Elea in southern Italy. He is known for being the founder of the Eleatic School of philosophy, which teaches a strictly monistic view of reality.

This principle is based on the belief that the world is one in substance, has not been created and is indestructible. In his vision change is not possible and existence is eternal, uniform and unchangeable. Parmenides was a disciple of Xenophanes of Colophon, but left his teacher to follow his own vision.

Anaximander

Anaximander (610 BC - 545 BC) was a pre-Socratic Greek philosopher who lived in Miletus in modern Turkey. He belonged to the School of Miletus and was a disciple of Thales.

In time he became a teacher of this same school and counted Anaximenes and Pythagoras among his pupils. He was a proponent of science and tried to observe different aspects of the universe, in particular its origins.

He believed that nature was controlled by laws, in the same way that human societies are, and any disturbance in the balance of it could not last long.

Empedocles

Empedocles (490 BC - 430 BC) was a philosopher and poet born in Acagras, in Greek Sicily. He was one of the most important philosophers who worked before Socrates and a poet of great skill and influence for later characters like Lucretius.

He is best known for being the creator of the classical cosmogonic theory of the four elements. He also proposed that the forces of love and conflict mix and separate each of the elements from each other. Influenced by the Pythagoreans, Empedocles was a vegetarian and supported the theory of reincarnation.

Anaxagoras

Anaxagoras (510 BC - 428 BC) was a pre-Socratic Greek philosopher born at Clazomenae in Asia Minor. He lived and taught in Athens for over 30 years. His vision described the world as a mix of imperishable primary ingredients.

The change was never caused by the absolute presence of a particular ingredient, but by the preponderance of one of them over the others. He introduced the concept of Nous (Mind) as an ordering force that moves and separates the original mixture, which had homogeneous characteristics.

Democritus

Democritus (460 BC - 370 BC) was a pre-Socratic Greek philosopher born in Abdera, Thrace. He is best known for his formulation of the atomic theory of the Universe, which is quite similar to the atomic structure proposed in the 19th century.

His contributions are difficult to distinguish from those of his mentor Leucippus, since both are mentioned together in various texts.

It is said that Plato had a rivalry with him and had all his books burned so that today only fragments of his work are known. Democritus is considered by many to be the father of modern science.

Zeno of Elea

Zeno of Elea (490 BC - 430 BC) was a pre-Socratic philosopher who was a member of the Eleatic school founded by Parmenides. He is known exclusively for the proposition of a great number of ingenious paradoxes, particularly those concerning motion.

He was also called as the inventor of dialectics and is credited with laying the foundations of modern logic. Aristotle was in contradiction with Zeno's ideas about movement and called them fallacies.

However, many thinkers and philosophers throughout the millennia keep their thoughts alive when trying to explain it.

Protagoras

Protagoras (490 BC - 420 BC) was a pre-Socratic Greek philosopher born in Abdera, Thrace. It is considered to be the first to promote the philosophy of subjectivism, arguing that the interpretation of reality is relative to each of the individuals in experience, judgment and interpretation.

Protagoras was the first to teach this point of view as a sophist. A sophist was a master of rhetoric, politics, and logician who served as a private tutor to young men from the wealthy classes.

Anaximenes of Miletus

Anaximenes of Miletus (585 BC - 528 BC) was a pre-Socratic Greek philosopher, considered the third of the School of Miletus and a disciple of Anaximander. Anaximenes is best known for his doctrine that air is the source of all things, differing from his predecessors such as Thales, who considered water as the source.

From this idea, he built a theory that explains the origin of nature, the earth and the heavenly bodies that surround it. Anaximenes also used her observations and reasoning to provide causes for natural phenomena such as earthquakes, lightning, and the rainbow.

Leucippus of Miletus

Leucippus of Miletus. Image source: Wikimedia.org.

Leucippus of Miletus (n. 5th century BC) is considered one of the first philosophers to develop a theory about atomism. This is based on the belief that all things are composed entirely of several indivisible and indestructible units called atoms.

Leucippus constantly appears as the teacher of Democritus, to whom he also formulated an atomic theory.

There has long been a debate about the existence of Leucippus, since his alleged contributions to atomic theory tend to be difficult to discern from those of Democritus.

Xenophanes of Colophon

See page for author, via Wikimedia Commons

Xenophanes of Colophon (570 BC - 475 BC) was a Greek philosopher, theologian, poet, and critic. Some of his writings account for a skepticism whereby traditional religious views were lampooned as human projections.

It established that humans were entities independent of the gods and that discoveries in science and other areas were the results of human work and not divine favors.

Regarding the physical world, Xenophanes wrote that the world was composed of two opposites: the wet and the dry. He also believed in the existence of an infinite number of worlds that did not overlap with time.

Gorgias

Gorgias of Leontino (485 BC - 380 BC) was a Sicilian philosopher, orator, and rhetorician. He is considered one of the founders of sophistry, a traditional movement associated with philosophy, which emphasizes the practical application of rhetoric in political and civil life.

Like other sophists, Gorgias was an itinerant who practiced in various cities, giving public exhibitions and charging for private talks and instructions. Their performances included spontaneous questions from the audience for impromptu responses.

Euclid

Euclid (b. 300 BC) was a Greek mathematician best known for being the "father of geometry." He lived and worked in Alexandria during the reign of Ptolemy I. "Elements" is one of his most influential works on the history of mathematics, becoming used as a reference book for teaching the subject from its publication until the beginning of the century. XX.

In this book, Euclid deduces the principles of what is now known as Euclidean geometry from a series of axioms.

Philolaus

Philolaus (470 BC - 385 BC) was a Greek Pythagorean philosopher and contemporary of Socrates. He was one of the three most important figures in the Pythagorean tradition, writing a rhetorical treatise on philosophy.

Philolaus was the first to declare that the earth was not the stationary center of the cosmos, but moved around a central fire along with the fixed stars, the five planets, the Sun, the Moon and a mysterious parallel earth.

He argued that the cosmos and the whole were made up of two basic kinds of things: limited things and unlimited things.

Crotona Alcmaeon

Alcmaeon of Crotona (b. 510 BC) was one of the most important natural philosophers and medical theorist of antiquity. He was the first to support the importance of the brain as the basis of consciousness and intelligence. He also came to practice the dissection of human bodies for research purposes.

For Alcmeon, the soul was the source of life. He also established that cosmic harmony is the harmony between opposing pairs and therefore human health consisted in the balance of opposing compounds in the body.

Archelaus

Archelaus (n. 5th century BC) was a Greek philosopher, a pupil of Anaxagoras and a possible teacher of Socrates. He is best known for establishing the principle that movement was the separation of hot from cold and from which he tried to explain the formation of the Earth and the creation of animals and humans.

Archelaus held that air and infinity were the beginning of all things. He also stated that the Earth was flat, but that the surface was depressed in the center. Del Sol even said that it was the largest of all the stars.

Brontinus

Brontinus of Metaponto (n. 6th century BC) was a Pythagorean philosopher and a disciple of Pythagoras himself. It is not known if he was the father or the husband of the philosopher Theano. Some Orphic poems are also recognized. Furthermore, he is credited with the point of view in which the monad, or first cause, transcended all types of reason and essence in power and dignity.

Damo

Damo (b. 500 BC) was a Pythagorean philosopher born in Crotona, who is believed to be the daughter of Pythagoras and Theano. Because in the school formed by her father, he took responsibility for the works of its members, many of the contributions created by her were attributed to him.

According to one story, Pythagoras inherited his writings from Damo, and she kept them by refusing to sell them, with the firm belief that the knowledge stored in them was more valuable than gold.

Diogenes of Apollonia

Diogenes of Apollonia (b. 425 BC) was a Greek philosopher born in the Greek colony of Apollonia in Thrace. He believed that air was the sole source of all existence and as a primary force, possessed intelligence.

All other substances in the universe were derived from the air by means of condensation and rarefaction. Diogenes also held that there are an infinite number of worlds, as well as an infinity of emptiness.

As for the Earth, he believed that it was round and its shape was the product of the spinning of hot vapors on it.

Hermotimus of Clazómenas

Hermotimus of Clazómenas (n. 6th century BC) was a philosopher who proposed that physical entities are static and it is the mind that causes change. Hermotimus belongs to a class of philosophers who held a dual theory of a material principle and an active one as causes of the universe.

Hippo

Hipón (n. 5th century BC) was a pre-Socratic Greek philosopher and is related to having been born in Regio, Metaponto, Samos or Crotona. It is also possible that there has been more than one philosopher with this name.

Although he was a natural philosopher, Aristotle refused to place him along with other pre-Socratic philosophers because of the "insignificance of his thoughts." He was accused of atheism, but since there is no record of his texts, it is not possible to know why.

He believed that water and fire were the primary elements, water being the origin of fire and this developing to be the beginning of all things. He also showed interest in biology, and stated that all living things have an adequate level of humidity to function.

Meliso from Samos

Meliso of Samos (n. 5th century BC) was the third and last member of the Eleatic school of philosophy. It is known that he was the commander in a fleet of ships just before the Peloponnesian War.

Like Parmenides, Meliso established that reality has always existed, is indestructible, indivisible, and remains still without change. He came to propose that existence is unlimited and extends to infinity in all directions.

His thoughts were written in prose and not in poetry as Parmenides did, and of them only 10 fragments are preserved.

Chios Metrodoro

Metrodoro of Chios (n. IV century BC) was a Greek philosopher belonging to the school of Democritus and predecessor of Epicurus. It is considered that he was a pupil of Nessus of Chios or some believe that of Democritus himself.

Metrodoro was considered a skeptic and included among his concepts the theory of atoms and the void and the plurality of worlds. He also supported the theory that stars were formed day by day by moisture in the air from the heat of the Sun.

He is credited with having had an advanced cosmological vision for his time, holding that "a single piece of wheat in a large field is as strange as a single world in infinite space."

Lámpsaco Metrodoro

Metrodoro of Lámpsaco (331 BC - 277 BC) was a Greek philosopher of the Epicurean school. His belief was that perfect happiness came from having and maintaining a well-built body. He found himself in conflict with his brother for not admitting that the womb was a test and measure of the things that belonged to a happy life.

Myia

Myia (b. 500 BC) was a Pythagorean philosopher daughter of Theano and Pythagoras. She was married to Milo de Crotona, an athlete. A letter dating from the 2nd century BC is attributed to Myia and addressed to a certain Phyllis. This describes how the needs of a newborn should be met in accordance with the principles of harmony.

According to her, a baby naturally wants things in moderation and the one who takes care of them should attend to those needs with the same moderation.

Ferécides of Syros

Freécides de Siros (n. VI century BC) was a Greek thinker born on the island of Syros. Its main contribution is a cosmogony derived from three divine principles known as Pentemic: Zas (Zeus), Cthonie (Earth) and Chronos (Time).

This constituted a union between the mythological thought of Hesiod and the pre-Socratic philosophy. No direct samples of his work are preserved, but this is referenced by philosophers of the Hellenistic period.

He was the first thinker who is recognized for communicating his philosophical reflections in a prosaic style.

Prodic of Ceos

Prodicus of Ceos (465 BC - 395 BC) was a Greek philosopher known to be part of the first generation of Sophists. He came to Athens as a Ceos ambassador and quickly became known as a speaker and teacher.

Plato considers Prodicus with great respect above other sophists and in his dialogues, Socrates appears as his friend. He is recognized for his bearing on linguistic theory and his insistence on the correct use of words.

In the same way as other sophists, Prodicus interpreted religion as the personification of the Sun, the Moon, the rivers, the fountains and any other element that brought comfort to life.

Antiphon, the sophist

Antiphon (480 BC - 411 BC) was a Greek orator and philosopher who lived in Athens. One of his texts on political theory is of importance for being the forerunner of the theory of natural rights.

His vision expresses principles of equality and freedom associated with democracy. Nature is seen as an entity that requires spontaneity and freedom, in contrast to the restrictions that are imposed by institutions.

Antiphon was also a mathematician and was the first to assign an upper and lower limit to the value of pi.

References

1. O'Grady, Patricia. Internet Encyclopedia of Philosophy. iep.utm.edu.
2. Stanford Encypclopedia of Philosophy. Heraclitus. February 8, 2007. plato.stanford.edu.
3. Mark, Joshua J. Ancient History Encyclopedia. Parmenides. April 28, 2011. ancient.eu.
4. Today in Science History. Metrodorus of Chios. todayinsci.com.
5. Filosofia.org. Disciples and Successors of Epicurus. 2002. philosophy.org.